The "killer app" of current nanotechnology is the carbon nanotube, which could revolutionize circuit boards and other technologies. But these nanoscopic tubes also cause a new kind of industrial disease that could scar your lungs and give you cancer.
Carbon nanotubes have been proposed for use in everything from space elevators to synthetic muscles to sports equipment. But a new study shows that they can severely damage lungs if inhaled. There have long been fears that the nanotubes might cause mesothelioma, cancer of the lining of the lungs, because of their structural similarity to asbestos fibers. Now research has shown significant health risks from the tubes, which confirms previous studies about the dangers of this comparatively simple nanotech.
The research comes out of North Carolina State University, and is published in this month's Nature Nanotechnology. It showed that within a day of exposure, mice's lungs were reacting to the particles, with clusters of immune cells gathering on the outer walls (pleura) of their lungs. Within two weeks, fibrosis, or localized scarification, had occurred. This same scarring occurs after exposure to asbestos. Three months after this single exposure, the scarification and immune response had dissipated. However, chronic exposure might lead to a different result, with cancer as one possible outcome. And chronic exposure is exactly what humans have to worry about, when carbon nanotubes are rolled out for use in a variety of technologies. Workers may be exposed to the tiny tubes every day.
Previous studies out of the UK and Japan show similar results: that the nanotubes have a nasty habit of reaching the outer tissue of your lungs, the same location where asbestos causes cancer. The Japanese study from 2007 is particularly damning, as researchers were able to induce mesothelioma in mice using the carbon nanotubes.
Given the already-existing issues with asbestos remaining in the environment, and the unknown ecological impact of carbon nanofibers, this raises very troubling issues for the tube's long term effects. As useful as they may be, what will happen if they have a tendency to hang around in the local ecosystem for a very long time? Will its potentially damaging side effects overrule the mammoth benefits it may have in modern production? What about the safe disposal of objects containing nanotubes? If they do become ubiquitous, getting rid of the things may be a major problem. For all the fears of grey goo, it might just be one of the simplest forms of nanotech that does us in.